dmaengine: ste_dma40: limit burst size to 16

The client is not aware of the maximum burst size in the dma driver.  If
the size exceeds 16 set max to 16.
Signed-off-by: Per Forlin <per.forlin@stericsson.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Fabio Baltieri <fabio.baltieri@linaro.org>

drivers/dma/ste_dma40.c

@@ -2578,6 +2578,14 @@ static int d40_set_runtime_config(struct dma_chan *chan,
 		return -EINVAL;
 	}
 
+	if (src_maxburst > 16) {
+		src_maxburst = 16;
+		dst_maxburst = src_maxburst * src_addr_width / dst_addr_width;
+	} else if (dst_maxburst > 16) {
+		dst_maxburst = 16;
+		src_maxburst = dst_maxburst * dst_addr_width / src_addr_width;
+	}
+
 	ret = dma40_config_to_halfchannel(d40c, &cfg->src_info,
 					  src_addr_width,
 					  src_maxburst);